This is only going to apply to clowns that I have actually owned, and sure my examples will be different then others.
Mean to me
Cinnamon --- meanest fish I have ever had. Would bite -- blood, headbutt, and do anything that it could to tick me off.
GSM pair --- similar to the Cinnamon, just not as violent
B&W Os pair --- both would drew blood, but due to their size it wasn't as bad.
Pink skunks pair --- never attacked me directly, but anytime I am near the tank they will "bark" at me.
Clarkii pair --- pretty mellow, though as I am talking my hand out of the tank they will chase after it --- and not even come close. I guess it makes them feel like they chased me out.
SI True perc pair --- Could care less about me, though do seem to think that anytime I am near, or in the tank they are going to get feed.
To other fish/corals
GSM pair --- can't say, were in a tank by themselves.
Clarkii pair --- New additions are attacked. Established fish are pushed away from their anemone. And will attack any fish that goes after a different anemone on the other side of the tank (( that anemone normally doesn't host anything )). Will remove any coral (( or attempt to if large )) that is placed within a foot of their anemone.
Cinnamon -- similar to above, but since it was a single clown it wasn't as bad.
Pink skunk pair --- A while back I added a smaller Potter's angel to pair up with my existing one. They attacked it a lot more then the existing Potter's. Have yet to re-arrange corals.
B&W Os --- didn't seem to care about other fish & corals. In fact, once in a blue moon my Flameback angel would go into their LTA, they didn't care.
SI True percs --- very mellow. My tailspot blenny's "home" is near their LTA, they could care less. (( or is it, couldn't ))